Semiconductor package and method for forming the same

1 . A method for forming a semiconductor package, comprising:

forming a first photonic routing structure over a substrate, comprising:

forming a curved surface over the substrate;

forming an oxide layer over the curved surface;

recessing the oxide layer to expose the curved surface; and

forming a reflective element over the curved surface;

disposing the first photonic routing structure over a redistribution structure, wherein the first photonic routing structure comprises a first waveguide;

disposing a second photonic routing structure and an optical engine die on the redistribution structure, wherein the second photonic routing structure comprises a second waveguide optically coupled to the first waveguide; and

forming a molding structure between the first photonic routing structure and the second photonic routing structure.

2 . The method for forming a semiconductor package as claimed in claim 1 ,

wherein the molding structure is formed between the substrate and the optical engine die.

3 . The method for forming a semiconductor package as claimed in claim 1 , wherein the molding structure comprises optical clear adhesive.

4 . The method for forming a semiconductor package as claimed in claim 1 , further comprising forming a dielectric layer between the substrate and the first photonic routing structure.

5 . The method for forming a semiconductor package as claimed in claim 1 , wherein the first photonic routing structure comprises a mirror formed by high-refractive coating film, and the substrate has a curved surface arranged with the mirror in a first direction perpendicular to the substrate.

6 . The method for forming a semiconductor package as claimed in claim 5 , wherein the mirror is arranged with the first waveguide in a second direction different from the first direction.

7 . A method for forming a semiconductor package, comprising:

forming a redistribution structure on a substrate;

disposing a first photonic routing structure on the redistribution structure, comprising:

forming a recess having a curved surface in an optical interposer die;

forming a first dielectric structure covering the curved surface, wherein a first waveguide is embedded in the first dielectric structure; and

forming a reflective element over the first dielectric structure;

disposing a second photonic routing structure and an optical engine die on the redistribution structure, wherein the second photonic routing structure comprises a second dielectric structure and a second waveguide disposed in the second dielectric structure, the optical engine die is disposed on the second photonic routing structure, and the second waveguide is optically coupled to the first waveguide and the optical engine die.

8 . The method for forming a semiconductor package as claimed in claim 7 , further comprising forming an anti-reflection layer in the first dielectric structure.

9 . The method for forming a semiconductor package as claimed in claim 8 , wherein forming the anti-reflection layer comprises:

recessing the first dielectric structure to form an opening; and

forming the anti-reflection layer on sidewalls of the opening.

10 . The method for forming a semiconductor package as claimed in claim 9 , wherein a curved surface of the optical interposer die is exposed from the opening, and the curved surface is spaced apart from the anti-reflection layer.

11 . The method for forming a semiconductor package as claimed in claim 7 , further comprising recessing a first surface of the optical interposer die to form a recess, wherein the recess has a curved bottom surface, and the first surface faces the first photonic routing structure.

12 . The method for forming a semiconductor package as claimed in claim 7 , further comprising forming an anti-reflection layer on sidewalls of the recess.

13 . The method for forming a semiconductor package as claimed in claim 7 , wherein a third waveguide is formed in the redistribution structure and optically coupled to the first waveguide and the second waveguide.

14 . The method for forming a semiconductor package as claimed in claim 7 , wherein a direction that the curved surface arranged with the reflective element is different from a direction that the reflective element arranged with the second waveguide.

15 . A semiconductor package, comprising:

a first substrate;

a redistribution structure formed on the first substrate;

a first photonic routing structure disposed on the redistribution structure, comprising:

a second substrate having curved surface;

a first dielectric structure disposed over the second substrate, wherein the curved surface faces the first dielectric structure;

a first waveguide disposed in the first dielectric structure; and

a reflective element disposed in the first dielectric structure and overlapping the curved surface;

an optical interposer die disposed on the first photonic routing structure;

a second photonic routing structure disposed on the redistribution structure, wherein the second photonic routing structure comprises a second dielectric structure and a second waveguide disposed in the second dielectric structure and optically coupled to the first waveguide;

an optical engine die disposed on the second photonic routing structure; and

a molding structure disposed between the first photonic routing structure and the second photonic routing structure.

16 . The semiconductor package as claimed in claim 15 , wherein the first photonic routing structure further comprises:

a reflective element disposed in the first dielectric structure.

17 . The semiconductor package as claimed in claim 15 , wherein the optical interposer die and the optical engine die are arranged in a direction parallel to a surface of the substrate.

18 . The semiconductor package as claimed in claim 15 , wherein the optical engine die comprises a photonic die disposed on the second photonic routing structure and an electric die disposed on the photonic die, wherein the photonic die and the electric die have different widths.

19 . The semiconductor package as claimed in claim 18 , wherein the optical interposer die covers a portion of the second photonic routing structure and the molding structure.

20 . The method for forming a semiconductor package as claimed in claim 1 , wherein the second waveguide is optically coupled to the optical engine.